The study of olfaction in aging and Alzheimer's disease (AD) is a relatively new area of investigation. It appeal that some AD subject have deficits in order identification which may be due to damage to the olfactory bulb as a result of abnormal detoxification mechanisms. Studies will determine whether the various enzymes in this detoxification pathway are either suppressed or activated in post-mortem tissues from AD patients and normal age-matched controls. The implications of this study would suggest possible mechanisms for the etiology of AD. It may be possible to monitor these enzyme markers in biopsies olfactory epithelium from AD patients.